feat: add --env and --preset support to hermes mcp add

- Add --env KEY=VALUE for passing environment variables to stdio MCP servers
- Add --preset for known MCP server templates (empty for now, extensible)
- Validate env var names, reject --env for HTTP servers
- Explicit --command/--url overrides preset defaults
- Remove unused getpass import

Based on PR #7936 by @syaor4n (stitch preset removed, generic infra kept).

hermes_cli/mcp_config.py

@@ -9,7 +9,6 @@ configuration in ~/.hermes/config.yaml under the ``mcp_servers`` key.
 """
 
 import asyncio
-import getpass
 import logging
 import os
 import re
@@ -28,6 +27,11 @@ from hermes_constants import display_hermes_home
 
 logger = logging.getLogger(__name__)
 
+_ENV_VAR_NAME_RE = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*$")
+
+
+_MCP_PRESETS: Dict[str, Dict[str, Any]] = {}
+
 
 # ─── UI Helpers ───────────────────────────────────────────────────────────────
 
@@ -98,6 +102,59 @@ def _env_key_for_server(name: str) -> str:
     return f"MCP_{name.upper().replace('-', '_')}_API_KEY"
 
 
+def _parse_env_assignments(raw_env: Optional[List[str]]) -> Dict[str, str]:
+    """Parse ``KEY=VALUE`` strings from CLI args into an env dict."""
+    parsed: Dict[str, str] = {}
+    for item in raw_env or []:
+        text = str(item or "").strip()
+        if not text:
+            continue
+        if "=" not in text:
+            raise ValueError(f"Invalid --env value '{text}' (expected KEY=VALUE)")
+        key, value = text.split("=", 1)
+        key = key.strip()
+        if not key:
+            raise ValueError(f"Invalid --env value '{text}' (missing variable name)")
+        if not _ENV_VAR_NAME_RE.match(key):
+            raise ValueError(f"Invalid --env variable name '{key}'")
+        parsed[key] = value
+    return parsed
+
+
+def _apply_mcp_preset(
+    name: str,
+    *,
+    preset_name: Optional[str],
+    url: Optional[str],
+    command: Optional[str],
+    cmd_args: List[str],
+    server_config: Dict[str, Any],
+) -> tuple[Optional[str], Optional[str], List[str], bool]:
+    """Apply a known MCP preset when transport details were omitted."""
+    if not preset_name:
+        return url, command, cmd_args, False
+
+    preset = _MCP_PRESETS.get(preset_name)
+    if not preset:
+        raise ValueError(f"Unknown MCP preset: {preset_name}")
+
+    if url or command:
+        return url, command, cmd_args, False
+
+    url = preset.get("url")
+    command = preset.get("command")
+    cmd_args = list(preset.get("args") or [])
+
+    if url:
+        server_config["url"] = url
+    if command:
+        server_config["command"] = command
+    if cmd_args:
+        server_config["args"] = cmd_args
+
+    return url, command, cmd_args, True
+
+
 # ─── Discovery (temporary connect) ───────────────────────────────────────────
 
 def _probe_single_server(
@@ -166,13 +223,35 @@ def cmd_mcp_add(args):
     command = getattr(args, "command", None)
     cmd_args = getattr(args, "args", None) or []
     auth_type = getattr(args, "auth", None)
+    preset_name = getattr(args, "preset", None)
+    raw_env = getattr(args, "env", None)
+
+    server_config: Dict[str, Any] = {}
+    try:
+        explicit_env = _parse_env_assignments(raw_env)
+        url, command, cmd_args, _preset_applied = _apply_mcp_preset(
+            name,
+            preset_name=preset_name,
+            url=url,
+            command=command,
+            cmd_args=list(cmd_args),
+            server_config=server_config,
+        )
+    except ValueError as exc:
+        _error(str(exc))
+        return
+
+    if url and explicit_env:
+        _error("--env is only supported for stdio MCP servers (--command or stdio presets)")
+        return
 
     # Validate transport
     if not url and not command:
-        _error("Must specify --url <endpoint> or --command <cmd>")
+        _error("Must specify --url <endpoint>, --command <cmd>, or --preset <name>")
         _info("Examples:")
         _info('  hermes mcp add ink --url "https://mcp.ml.ink/mcp"')
         _info('  hermes mcp add github --command npx --args @modelcontextprotocol/server-github')
+        _info('  hermes mcp add myserver --preset mypreset')
         return
 
     # Check if server already exists
@@ -183,13 +262,15 @@ def cmd_mcp_add(args):
             return
 
     # Build initial config
-    server_config: Dict[str, Any] = {}
     if url:
         server_config["url"] = url
     else:
         server_config["command"] = command
         if cmd_args:
             server_config["args"] = cmd_args
+        if explicit_env:
+            server_config["env"] = explicit_env
+
 
     # ── Authentication ────────────────────────────────────────────────
 
@@ -627,6 +708,7 @@ def mcp_command(args):
         _info("hermes mcp serve                              Run as MCP server")
         _info("hermes mcp add <name> --url <endpoint>        Add an MCP server")
         _info("hermes mcp add <name> --command <cmd>         Add a stdio server")
+        _info("hermes mcp add <name> --preset <preset>       Add from a known preset")
         _info("hermes mcp remove <name>                      Remove a server")
         _info("hermes mcp list                               List servers")
         _info("hermes mcp test <name>                        Test connection")